Police said Hernandez stepped in when he saw Zamora fighting with his mother outside, using Mace on the teen after he grew aggressive, CNN reports. That’s when Zamora is accused of going inside the house, returning with a gun and shooting Hernandez in the stomach — then fleeing the home as SWAT officers arrived, according to CNN. Efforts to resuscitate Hernandez failed.

Zamora has “an extensive violent criminal history,” according to KOAT, including reports of slapping and punching his mother. He faces murder charges, KOB reports.

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“It was a shock. I think we were all in shock, and I think we still are,” said his brother Martin Hernandez, according to the TV station. “He was a big guy, he was taller than I was and a lot broader from the shoulders, and he just had a really big personality that matched his size.”

His brother said he wasn’t shocked to learn Hernandez died trying to help another person, the TV station reports.

“When we found out that this happened to him, we felt that that was a way that if he were to choose a way to leave this earth, it would probably be doing something like that,” his brother told KRQE.

Albuquerque police said local officers and the U.S. Postal Inspection Service arrested Zamora on Wednesday night “without incident,” the Albuquerque Journal reports.

A Postal Service spokesman said Hernandez, a Phoenix native, had worked in Albuquerque for the federal agency for 12 years, according to the newspaper.

Those along Hernandez’s route and beyond have created makeshift memorials, according to KRQE reporter Chris McKee.

Another memorial for Hernandez has sprung up at the Five Points post office. In SW ABQ, off of Bridge Blvd. A handwritten message reads, “Till we meet again, I love you my brother.” pic.twitter.com/RKohK3iudI

Albuquerque Mayor Tim Keller said in a statement that locals should “take some time in the next few days to personally make sure your local letter carrier knows how much you appreciate them, and give them your love and support.”

“This tragic shooting has shaken our city. We are grieving with the family of the victim, and with the entire postal service family,” Keller said. “While we are working to get answers to the many remaining unanswered questions, we know we must, and will continue to, fight against the gun violence that has taken a terrible toll on our community.”

KOAT reports that Zamora could face charges in federal court because Hernandez was a federal government employee.

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